An image grab taken from AFP TV shows shoppers raising their arms as they are evacuated Sept. 21 from the Westgate mall in Nairobi. / AFP/Getty

by Gary Strauss, Donna Leinwand Leger and Kevin Johnson , USA TODAY

by Gary Strauss, Donna Leinwand Leger and Kevin Johnson , USA TODAY

Somalis in the United States are condemning the deadly attack on a Kenyan shopping mall tied to the extremist al-Shabab Islamist group based in their homeland. Yet they and others also fear the latest battlefront on terrorism could radicalize more of their own here.

It's unclear whether Somali Americans are part of the al-Shabab assault that has killed at least 62 people and wounded scores more in a Nairobi siege that extended to four days Tuesday.

Kenyan Foreign Minister Amina Mohamed said Monday on PBS' NewsHour that "two or three Americans" and "one Brit" were among the militants involved in the attack. She said the Americans were 18 to 19 years old, of Somali or Arab origin and lived "in Minnesota and one other place" in the United States.

The FBI said Monday evening that it has no confirmation of Americans' involvement in the attack but is still reviewing the situation.

A Sunday Twitter posting said several of the attackers - including two Minnesota men - were Somalis recruited from America. But al-Shabab said in a Monday Tweet that it had not sent the earlier message and didn't identify any of the dozen or so mall attackers. At least three attackers have been killed and several others arrested by Kenyan forces who stormed the mall to rescue hostages.

The reports of possible American involvement unnerved Somali refugees who've settled in Minneapolis; Columbus, Ohio; and other American cities since 1991. Metropolitan Minneapolis, the nation's largest outpost for Somalis, has been a recruiting conduit for al-Shabab since 2007, with at least 20 young men having disappeared, according to the FBI.

"Any time there is (al-Shabab) terrorist action, the whole community is anxious, sad and afraid,'' said Abdirizak Ali Bihi, executive director of the Minneapolis' Somali Education and Social Advocacy Center. "Our hope is this doesn't involve one of those stupid kids."

The Somali community in Minneapolis, which numbers up to 100,000, plans a Friday rally denouncing al-Shabab.

Bihi, whose 17-year-old nephew was recruited as an al-Shabab suicide bomber and is believed to have died in 2008, said outreach programs and law enforcement have helped curb the terrorist organization's recruiting efforts, but young Somali men remain vulnerable due to poverty, high unemployment rates and disenfranchisement with American society.

Bihi and Mohamud Noor, executive director of the Confederation of Somali Community in Minnesota, fear the potential connection to Somali Americans will cause a backlash against local Somali residents.

"We are concerned about the safety of the community," Noor said.

In Columbus, the center for many of the state's 45,000 Somalians, there are similar worries. Said Hassan Omar, head of the Somalia Community Association of Ohio: "Al-Shabab is a threat to everybody -- they are murderers. The reason we came to this country was because of the violence that was taking place in Somalia."

Somali President Hassan Sheikh Mohamud, in Columbus to deliver a speech at Ohio State University, said al-Shabab is a global threat.

Mohamud cited an al-Shabab assault on Somalia's main court complex in April that killed dozens and a 2010 attack in Uganda's capital that killed 76.

The attack in Kenya has sparks feared among non-Somalis as well.

"People feel threatened,'' Omar said. "We don't want our neighbors, our co-workers or our children's classmates to be scared. America has given us an opportunity to have a better life. We love this country."

Terrorism expert J. Peter Pham, director of the Atlantic Council Africa Center, said the Nairobi attack could serve as an international recruiting tool for young Somalis living in the U.S.

"The publicity that comes from this can be used to recruit the audience of young, marginalized men who are not incorporated into American society,'' Pham said. "They're prone to the sophisticated use of Twitter and YouTube."

Indeed, Alabama-born Abu Mansoor Al-Amriki was a key al-Shabab recruiter, using the Internet until he reportedly denounced the organization. His death was announced just two weeks ago.

Al-Shabab's recruiting drive has not ended well for several ethnic Somali men from the Minneapolis area.

In May, four men were sentenced in Minneapolis for providing support to al-Shabab, including money and men.

"These defendants, by providing material support to a designated terrorist organization, broke both the law and the hearts of family members across the Twin Cities,'' then-Minnesota U.S. Attorney B. Todd Jones said. "They facilitated the travel of other men to Somalia to fight or they themselves traveled to fight, often leaving Minnesota in the dead of night, without so much as a word to their parents."

Their convictions were linked to a federal investigation known as "Operation Rhino,'' which focused on the disappearance of several young, ethnic Somalis from the region since October 2007, others between February 2008 and October 2009, according to an FBI summary.

In July 2008, federal authorities said, men from Minneapolis participated in an al-Shabab ambush of Ethiopian troops. On Oct. 29, 2008, one of the men, Shirwa Ahmed, detonated an improvised explosive device in one of five coordinated suicide bombings in Bosaso and Hargeisa, Somalia. Ahmed is believed to have become the first American suicide bomber in Somalia.

And in May 2011, Farah Mohamed Beledi, who left Minnesota in October 2009, was killed at a checkpoint in Somalia as he attempted to detonate a suicide vest.